rs80338705

chr16-8847737-A-Gchr16-8847737-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PM5

The NM_000303.3(PMM2):c.653A>G(p.His218Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000109 in 1,461,350 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H218L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000011 (0 hom.)
• Consequence: PMM2 NM_000303.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.74

Genes affected

PMM2 (HGNC:9115): (phosphomannomutase 2) The protein encoded by this gene catalyzes the isomerization of mannose 6-phosphate to mannose 1-phosphate, which is a precursor to GDP-mannose necessary for the synthesis of dolichol-P-oligosaccharides. Mutations in this gene have been shown to cause defects in glycoprotein biosynthesis, which manifests as carbohydrate-deficient glycoprotein syndrome type I. [provided by RefSeq, Jul 2008]

(HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 7 uncertain in NM_000303.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-8847736-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 92805.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMM2	NM_000303.3	c.653A>G	p.His218Arg	missense_variant	8/8	ENST00000268261.9
PMM2	XM_047434215.1	c.404A>G	p.His135Arg	missense_variant	6/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMM2	ENST00000268261.9	c.653A>G	p.His218Arg	missense_variant	8/8	1	NM_000303.3	P1
	ENST00000567942.1	n.343T>C		non_coding_transcript_exon_variant	2/2	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251246 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135834

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000109 AC: 16 AN: 1461350 Hom.: 0 Cov.: 30 AF XY: 0.00000825 AC XY: 6 AN XY: 727016

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000135

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.39
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.24
Cadd	Uncertain	24
Dann	Uncertain	0.98
DEOGEN2	Pathogenic	0.87	D;D;.
Eigen	Benign	0.17
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.91	D;D;D
M_CAP	Pathogenic	0.29	D
MetaRNN	Uncertain	0.69	D;D;D
MetaSVM	Pathogenic	0.89	D
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Benign	0.47	T
PROVEAN	Pathogenic	-5.3	D;D;D
Sift	Uncertain	0.0010	D;D;D
Sift4G	Uncertain	0.0050	D;D;D
Polyphen		0.014	.;B;.
Vest4		0.52
MutPred		0.80		.;Loss of sheet (P = 0.1158);.;
MVP		0.93
MPC		0.0076
ClinPred		0.96	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.94
gMVP		0.84

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs80338705; hg19: chr16-8941594;